The administration of local anesthetics is an indispensable step of dental practice, however, it is always not a good experience to both dentists and patients. There exist various types of dental anaesthetic injection device in the market, among others, a manual (thumb-palm) driven injection device and a computer based injection device are well known in the art.
The injection device of manual driven type may cause occupational injuries to the dentists at their fingers joints exerting forces while controlling the plunger of the syringe holder. In addition, it is hard for the dentists to maintain the stability of an injecting hand while the same hand is required to exert full effort in manipulating the injection device or the plunger of the syringe holder thereof. As a result, injection of the anaesthetic by using such an injection device is hard to proceed smoothly in producing a painless injection. Also, the patients find agony in receiving a dental local anaesthesia, which ends up in low patients' return rate and compliance.
The injection device of computer based type is expensive and computer dependent, which causes additional costs and renders operational difficulties to the dentists, because most of the dentists are now practicing without a computer and in turn do not get used to computer operations, although such computer based systems can bring the advantages of automation and precise dosage control of the injection. Consequently, the majority of dental professionals worldwide are still using a traditional thumb-and-palm grasping cartridge-syringe system out of financial consideration and due to its low technical requirements.
Because of the mechanism of the traditional anaesthetic injection device described above, most of the dentists have an early onset of occupational health problems such as Carpal Tunnel Syndrome. The frequent wearing of thumb and palm tendon leads the dentists to the development of tendonitis, an illness that is preventable if attended earlier.
Another drawback of the traditional anaesthetic injection device is its limited ability in successful controlling of the pressure, rate, volume and the tissue penetration of the injection. This leads to an agony of pain sensation applied to the patients while receiving the injection of anesthetics.
Therefore, there exists a need for developing a pneumatic anaesthetic delivery system which is easy to install and operate and structurally simple, and which does not require a computer nor any additional electronic device. Such a system is able to not only save the dentists from career trauma, but also alleviate pain in the patients.